Elatostema laxicymosum W. T. Wang

Herbs perennial, dioecious, 40-50 cm tall, glabrous. Stems ascending or erect, simple or branched. Leaves alternate; nanophylls absent; stipules subulate, 4-7 × 0.1-0.2 mm, with cystoliths; petiole 0-3 mm; leaf blade obliquely elliptic or obovate-elliptic, 5.5-13 × 2.5-5 cm, herbaceous or papery, major basal lateral veins asymmetric, 1 basal, the other arising above base, cystoliths conspicuous, dense; base with broader half broadly cuneate, margin serrate, apex acuminate. Male inflorescences solitary, branched, 10-22 mm in diam.; peduncle 30-65 mm; receptacle absent; bracts alternate, narrowly linear, 2.5-4 mm. Female inflorescences solitary, 5-11 × 4-7 mm; peduncle ca. 1.2 mm; receptacle nearly oblong, ca. 8 × 6 mm; bracts linear; bracteoles spatulate-linear. Male flowers 4-merous. Achenes narrowly ovoid, 10-ribbed. Fl. Aug-Dec.

SE Xizang [N India].

Evergreen broad-leaved forests or lake banks; 600-2200 m.

Elatostema laxicymosum là loài thực vật có hoa trong họ Tầm ma. Loài này được W.T.Wang mô tả khoa học đầu tiên năm 1979.

疏伞楼梯草（学名：Elatostema laxicymosum）为荨麻科楼梯草属的植物，是中国的特有植物。分布在中国大陆的西藏等地，生长于海拔800米至1,900米的地区，多生长于常绿阔叶林中及湖边，目前尚未由人工引种栽培。